JP2005058867A - Hydrogen-separable sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prepare a hydrogen-separable sheet in which the use quantity of vanadium is made lower than usual. <P>SOLUTION: This hydrogen-separable sheet is provided with: a base material part A1 which contains mainly stainless steel powder (a) and vanadium (Pd) powder (b) and is molded in a sheetlike shape having a predetermined thickness; and a hydrogen-permeable part A2 which is dispersed/arranged in the base material part A1 and in which vanadium (Pd) exposed to one side of this hydrogen-separable sheet is connected to vanadium exposed to the other side. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hydrogen separation sheet.

  As is well known, hydrogen separation membranes are used for obtaining high-purity hydrogen gas in semiconductor manufacturing and hydrogen gas as fuel for fuel cells. Conventionally, many technologies related to such hydrogen separation membranes have been developed and put into practical use. The common point of these conventional technologies is that a palladium (Pd) membrane, which is a rare metal, is formed on a porous substrate. is there.

For example, in Japanese Patent Application Laid-Open No. 2003-135943, as one of the above-described conventional techniques, a porous ceramic layer is formed on a metal porous body, and a palladium film or a palladium alloy is formed on the porous ceramic layer using a CVD method. A technique for forming a film is disclosed. According to this technique, the mechanical strength of the hydrogen separation membrane can be improved by laminating the metal porous body and the porous ceramic layer, while the thickness of the palladium membrane or the palladium alloy membrane is 0.3 to 5 μm. By setting to, good mechanical strength and hydrogen permeability are realized while suppressing the amount of palladium compound used.
Japanese Patent Laid-Open No. 2003-135943

By the way, palladium is a very expensive rare metal. Therefore, in order to reduce the cost of the hydrogen separation membrane, it is necessary to minimize the amount of palladium used. The technique disclosed in the above Japanese Patent Application Laid-Open No. 2003-135943 is also intended to suppress the amount of palladium compound, that is, palladium, but it is possible to further reduce the amount of palladium used than that technique. The development of is eagerly desired. In particular, cost reduction is an important issue in the production of hydrogen gas as a fuel for fuel cells. In order to realize a reduction in the production cost, the cost of a hydrogen separation membrane used in the production of hydrogen gas is important. Need to be reduced.

This invention is made | formed in view of the situation mentioned above, and aims at the following points.
(1) To provide a hydrogen separation sheet in which the amount of palladium used is reduced as compared with the prior art.
(2) To provide a hydrogen separation sheet that is less expensive than conventional ones.

  In order to achieve the above object, in the present invention, a base material portion mainly formed of stainless steel powder or nickel (Ni) powder and palladium (Pd) powder or palladium alloy powder and formed into a sheet having a predetermined thickness; And a hydrogen permeation part which is arranged in a distributed manner on the material part and exposed from palladium (Pd) or palladium alloy which is exposed on one side and is continuous with palladium (Pd) or palladium alloy which is exposed on the other side. Is adopted.

  According to the above solution, hydrogen is transmitted from one surface to the other surface by palladium (Pd) or a palladium alloy which is dispersedly arranged in the base material portion and is exposed on both surfaces and is continuous. Since such palladium (Pd) or palladium alloy is partially dispersed in the substrate portion, the palladium (Pd) or palladium alloy is more than the conventional hydrogen separation membrane having a palladium membrane or palladium alloy membrane on the entire surface. The amount used can be greatly reduced.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing an external configuration of a hydrogen separation sheet A according to the present embodiment, and FIG. 2 is an enlarged sectional view of the hydrogen separation sheet A.

  This hydrogen separation sheet A is formed into a sheet having a predetermined thickness as shown in FIG. 1 by using a powder rolling method. As shown in FIG. 2, the present hydrogen separation sheet A has a base material portion A1 formed of stainless steel powder a with a predetermined thickness, and is dispersedly arranged on the base material portion A1 and has a larger particle size than the stainless steel powder a. A single palladium (Pd) powder b is used to form a hydrogen permeable portion A2 in which palladium (Pd) is exposed on both sides.

  The base material part A1 made of a plurality of stainless powders a is a part that bears the mechanical strength of the hydrogen separation sheet A, while the hydrogen permeation part A2 made of palladium powders b exposed on both sides is one of hydrogen. It has a hydrogen permeation function that allows permeation from one surface to the other.

  FIG. 3 is an enlarged cross-sectional view of a hydrogen separation sheet B according to a modification of the present embodiment. This hydrogen separation sheet B is obtained by forming a mixed powder composed of stainless powder a1 and palladium (Pd) powder b1 having substantially the same particle size into a sheet having a predetermined thickness by using a powder rolling method. The hydrogen separation sheet B includes a base material part B1 mainly containing stainless powder a1 and palladium (Pd) powder b1 and formed into a sheet having a predetermined thickness, and is dispersedly arranged on the base material part B1. The palladium (Pd) powder b1 exposed on the surface is composed of a palladium (Pd) powder b1 exposed on the other surface and a hydrogen permeation part B2 connected through another palladium (Pd) powder b1.

  The base material part B1 mainly containing the stainless steel powder a1 containing the palladium (Pd) powder b1 is a part that bears the mechanical strength of the hydrogen separation sheet B, and a plurality of palladium (Pd) that connect both sides by connecting them. The hydrogen permeation part B2 made of the powder b1 has a hydrogen permeation function for permeating hydrogen from one surface to the other surface.

  FIG. 4 is a perspective view showing an external configuration of the hydrogen separation sheet C according to a further modification of the present embodiment. In this hydrogen separation sheet C, weld portions C1 made of stainless steel powder are provided at both ends of each of the hydrogen separation sheets A and B. The welded portion C1 is provided for welding both end portions of the hydrogen separation sheet C. That is, since palladium has a difficulty in weldability, it is possible to easily adhere and fix to the hydrogen separation sheet C by providing a welded portion C1 made of only a stainless material excellent in welding.

  Next, FIG. 5 is a system configuration diagram of a manufacturing apparatus S for manufacturing the hydrogen separation sheets A, B, and C. The manufacturing apparatus S includes a raw material powder supply hopper 1, a belt feeder 2, a pair of rolling rollers 3A and 3B, and a heating furnace 4. The raw material powder supply hopper 1 is disposed above one end of the belt feeder 2 and continuously supplies the raw material powder X onto the belt feeder 2 at a predetermined supply speed. The belt feeder 2 conveys and drops the raw material powder X supplied to one end by the raw material powder supply hopper 1 to just above the rolling rollers 3A and 3B.

  The rolling rollers 3 </ b> A and 3 </ b> B are arranged so that their peripheral surfaces face each other at a predetermined interval, and the raw material powder X dropped from directly above by the belt feeder 2 is rolled into a sheet. The heating furnace 4 is provided below the rolling rollers 3A and 3B, and heat-treats the raw material powder X (raw material sheet) formed by the rolling rollers 3A and 3B to improve the adhesion between the raw material powders X. Eliminate voids penetrating in the thickness direction of the sheet.

  The case where the hydrogen separation sheets A, B, and C are manufactured using such a manufacturing apparatus S will be described in more detail. First, the case where the hydrogen separation sheet A is manufactured will be described. In this case, the raw material powder X is a mixed powder composed of the stainless powder a and the palladium (Pd) powder b, and the palladium (Pd) powder b having a larger particle diameter than the stainless powder a is uniform in the stainless powder a. Are preprocessed to be distributed. Such raw material powder X is successively supplied to the recesses between the rolling rollers 3A and 3B via the raw material powder supply hopper 1 and the belt feeder 2, and is formed into a sheet.

  Here, since the hydrogen separation sheet A is in a state where each palladium (Pd) powder b is exposed on both sides as shown in FIG. 2, in the rolling process by the rolling rollers 3A and 3B, the raw material powder X is palladium ( Pd) Rolled to a thickness equal to or less than the particle size of powder b. Actually, the hydrogen separation sheet A is brought into the state shown in FIG. 2 in which the holes penetrating the front and back surfaces are eliminated by crushing and rolling the palladium (Pd) powder b by the pressing force during rolling. .

  Next, when manufacturing the hydrogen separation sheet B, the raw material powder X is a mixed powder composed of stainless powder a1 and palladium (Pd) powder b1 having substantially the same particle diameter, and the stainless powder a1 and palladium (Pd) powder b1. Are pre-processed so as to be mixed uniformly. Then, such raw material powder X is formed into a sheet by being successively supplied to the recess between the rolling rollers 3A and 3B via the raw material powder supply hopper 1 and the belt feeder 2.

  Next, when the hydrogen separation sheet C is manufactured, three partitions k1 to k3 continuous to the upper peripheral surface portion are provided by providing a partition plate on the upper peripheral surface portion of the rolling rollers 3A and 3B. Then, among these sections k1 to k3, the raw material powder X for the hydrogen separation sheet A or the hydrogen separation sheet B is supplied to the section k2 located in the middle, and the sections k1 and k3 located on both sides of the section k2 are supplied. Stainless powder a is supplied as raw material powder X, respectively. And each hydrogenated sheet | seat C is manufactured by rolling each such raw material powder | flour X with rolling roller 3A, 3B and making it into a sheet | seat.

In addition, this invention is not limited to the said embodiment, For example, the following modifications can be considered.
(1) The stainless steel powders a and a1 used for the production of the hydrogen separation sheets A, B and C may be nickel (Ni) powder.
(2) The palladium (Pd) powders b and b1 used for the production of the hydrogen separation sheets A, B and C may be palladium alloy powders. Further, vanadium (V) powder or vanadium (V) alloy powder may be used.

It is a perspective view which shows the external appearance structure of the hydrogen separation sheet A concerning one Embodiment of this invention. It is an expanded sectional view of hydrogen separation sheet A concerning one embodiment of the present invention. It is an expanded sectional view of the hydrogen separation sheet B concerning the modification of one Embodiment of this invention. It is an expanded sectional view of the hydrogen separation sheet C concerning the further modification of one Embodiment of this invention. It is a system block diagram of the manufacturing apparatus S provided for manufacture of the hydrogen separation sheet A, B, C concerning one Embodiment of this invention.

Explanation of symbols

A, B, C ... Hydrogen separation sheet a, a1 ... Stainless steel powder b, b1 ... Palladium (Pd) powder 1 ... Raw material powder supply hopper 2 ... Belt feeder 3A, 3B ... Rolling roller 4 ... Heating Furnace

Claims (2)

A base material portion mainly made of stainless steel powder or nickel (Ni) powder and palladium (Pd) powder or palladium alloy powder, and formed into a sheet of a predetermined thickness;
And a hydrogen permeation part which is dispersedly arranged on the base part and exposed continuously on one side of palladium (Pd) or palladium alloy exposed on the other side of palladium (Pd) or palladium alloy. Characteristic hydrogen separation sheet. 2. The hydrogen separation sheet according to claim 1, further comprising a welded portion made of stainless steel or nickel (Ni).

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